The invention relates to a rotary device for a rivet setting machine for self-punching rivets having a rotatable pick up device.
A pick up device for a setting machine has the function of picking up rivets in order to set them on a workpiece and fasten them there. With the aid of a C-bracket, which substantially has the shape of a large C and surrounds the workpiece, forces which act on the workpiece via a rivet during the setting process are absorbed on the opposite side of the workpiece. A feed tube is connected to the pick-up device and supplies the pick-up device with rivets.
It is known in the prior art to provide setting machines with a rotatable C-bracket in order to avoid a collision of the space-filling C-bracket with the workpiece. An orientating pin was provided on the C-bracket for stopping the pick-up device of the rotary device. Such an orientation of a pick-up device which used orientation pins was possible only with the use of a separate or special tool. In order to achieve free rotation of the pick-up device of the setting machine the prior art required that the orientation pin first be pulled out, then the pick-up device had to be rotated and, lastly, the orientation pin had to be inserted again. The problem with this was that changing the position of the pick-up device was time-intensive and manual intervention was often necessary, in particular when there was a danger of the supply line, such as for example the feed tube, touching the workpiece.
It is an object of the present invention to provide a rotary device for a rivet setting machine, in which a C-bracket and a pick-up device are rotatable relative to one another and can easily be stopped at different angle settings.
It is another object of the present invention to provide a rotary device for a rivet setting machine that is simple to make and to operate, that is economical to produce and is highly reliable in operation.
It is still another object of the present invention to provide a rotary device for a rivet setting machine that requires no separate or special tools.
The rotary device according to the invention for a rivet setting machine for self-punching rivets having a rotatable pick-up device with an angle of rotation lock, wherein the angle of rotation lock in the open state allows free rotation of the pick-up device relative to a C-bracket headpiece that is also rotatably mounted on the rivet setting machine, while in the closed state, stops the pick-up device at any predeterminable angular position with respect to the C-bracket headpiece. With the aid of the rotatable pick-up device the feed tube is appropriately turned away from a workpiece, so a collision of the feed tube with the workpiece is avoided. By means of the predeterminable angle settings the pick-up device can be stopped at any desired angle settings. With the aid of the angle of rotation lock stopping can be carried out in a simple manner and released to operate again without parts having to be pulled out or dismantled, so free rotation without complications and simple stopping is allowed.
In a further development of the invention the rotary lock has latching means, by which the pick-up device is stopped at any predeterminable angular setting. With the aid of the latching means certain angles of rotation can be predetermined, so simple setting of the angle of rotation of the pick-up device is possible and undesired distortion of the pick-up device is prevented.
In an advantageous further development at least one ball and at least one cavity are present as latching means, wherein by means of a guide non-rotatably connected dot the C-bracket headpiece the ball is movable only in a plane containing the axis of rotation of the rotary lock. Also, the cavity for the ball is located on a pick-up device holder non-rotatably connected to the pick-up device, so in the stopped state of the pick-up device the ball extends at least partially into the cavity, thus preventing rotation of the pick-up device relative to the C-bracket headpiece. Thus, the ball is movable by means of a guide in a plane containing the axis of rotation of the rotary lock, and in the stopped state of the pick-up device at least partially extends into the cavity, in the stopped state rotation of the pick-up device holder relative to the guide or the pick-up device relative to the headpiece is prevented. For example, the movement of the ball along the guide can take place directed radially outwards, away from the axis of rotation, or in the direction parallel to the axis of rotation of the pick-up device, or in combination of the two directions. Rotation of the pick-up device is in any case only possible if the ball does not extend into the cavity.
According to a special further development of the invention at least 8, in particular at least 15, preferably 24 cavities are present as latching means. The number of predeterminable angle positions is established by the number of cavities. For example with 24 cavities arranged so as to be equidistant the angle difference of two successive rotary positions of the angles of rotation is 15 degrees. In a further special development of the invention at least two, in particular four balls are present as latching means. The stability and rotational symmetry of the rotary stopping is increased by using a plurality of balls.
In a particular configuration of the invention the angle of rotation lock has at least one bolt by which the latching means are bolted. With the bolt a higher reliability of stopping with respect to an undesired movement of the pick-up device is achieved. In a special further development of the invention the bolt includes a guide in which the at least one ball is movable only in a plane containing the axis of rotation of the rotary lock.
In a further particular configuration of the invention the bolt is part of a ring surrounding the latching means. An annular structure is advantageous for the bolt in particular with configurations where the balls are movable radially inwards or outwards, as it has a particularly high stability with respect to twisting.
In a further advantageous configuration of the invention the ring can be moved in the direction parallel to the axis of rotation of the angle of rotation lock along grooves in the headpiece. The pick-up device holder is fastened to the headpiece by a groove nut.
In a further development of the rotary device according to the invention the bolt is held with the aid of at least one spring in a position in which the latching means are bolted. This prevents undesired rotation of the pick-up device.
Another feature of the present invention is that the angle of rotation lock can be opened and closed manually without the use of separate or special tools. This is particularly important if the rotary device is manually actuated and/or deactuated.
In a further configuration of the invention the angle of rotation lock can be automatically actuated (not shown), for example magnetically, pneumatically or hydraulically. A higher degree of automation is herewith achieved.